How much does Gemini 3.8 Flash cost compared to OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) per 1M tokens?

Gemini 3.8 Flash bills $0.27/1M input and $0.95/1M output ($0.027/1M cached read), whereas OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) bills $2.00/1M input and $8.00/1M output ($0.5/1M cached read). Choosing Gemini 3.8 Flash saves 87% ($314.00/month per 100M input + 20M output tokens).

How do Gemini 3.8 Flash and OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) perform with Context-Mode sandbox compression in Claude Code or Cursor?

Combining Context-Mode 98% tool-output folding (700KB -> 3.6KB) with Etuki 4-block prefix cache pinning reduces 100-session coding agent spend on Gemini 3.8 Flash from $51.05 to $3.59 (-93%), and on OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) from $382 to $33.5 (-91%).

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Gemini 3.8 Flash vs OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA): $0.27 vs $2.00 / 1M Tokens

Switching a 100M input / 20M output monthly workload from OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) to Gemini 3.8 Flash saves $314.00/month ($3768.00/year, -87%) on baseline token rates. For streaming responsiveness, Gemini 3.8 Flash leads with a 321ms P90 TTFT (131 tok/s).

Contender A • GEMINI

Gemini 3.8 Flash

Standard Input / Output:$0.27 / $0.95

Warm Cache Read / Write:$0.027 / $0.338

Batch API (50% Off):$0.135 / $0.475

Context Window & Cliff:200,000 tokens

P90 TTFT / Throughput:321ms / 131 tok/s

Open Gemini 3.8 Flash 6-Module Audit →

Contender B • OpenAI

OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA)

Standard Input / Output:$2.00 / $8.00

Warm Cache Read / Write:$0.5 / $2

Batch API (50% Off):$1 / $4

Context Window & Cliff:1,000,000 tokens

P90 TTFT / Throughput:410ms / 98 tok/s

Open OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) 6-Module Audit →

⚡ CONTEXT-MODE SANDBOX (315KB → 5.4KB) × ETUKI CACHE PINNING BENCHMARKOpen Full Context-Mode Calculator →

Coding Agent TCO (100 Sessions): Raw Tool Output (700KB) vs. Context-Mode + Etuki Prefix Cache

Execution Mode (100 Agent Sessions)	Gemini 3.8 Flash	OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA)	Architectural Mechanism
Mode A: Direct Raw Tool Output (700 KB)	$51.05	$382.00	47 × Read() dumped into context; hits 200K cliff
Mode B: Context-Mode Sandbox Only (3.6 KB)	$8.93	$60.00	SQLite FTS5 & ctx_execute (98% byte drop, unpinned cache)
Mode C: Context-Mode + Etuki 4-Block Cache Lock	$3.59 (-93%)	$33.50 (-91%)	98% tool stdout folding + 90% warm 0.1x prefix cache hit

Monthly Enterprise Workload TCO: Gemini 3.8 Flash vs OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA)

Workload Scenario	Gemini 3.8 Flash (Cached)	OpenAI GPT 6.1 Terra (Mapped to OpenAI GPT-4.1 GA) (Cached)	Recommended Routing Winner
① Coding Agent (15M In / 3M Out)	$3.98/mo	$36.00/mo	Gemini 3.8 Flash
② Enterprise RAG (100M In / 15M Out)	$21.81/mo	$200.00/mo	Gemini 3.8 Flash
③ Long-Doc SEC Analysis (250M In / 30M Out)	$47.40/mo	$440.00/mo	Gemini 3.8 Flash
④ Async Batch Pipeline (500M In / 80M Out)	$105.50/mo	$820.00/mo	Gemini 3.8 Flash (50% Batch Discount)